How do you make 1uh coil as it is not available in market?

To make a 1 µH coil, you can wind insulated copper wire around a cylindrical form, such as a plastic or cardboard tube. The number of turns and the diameter of the coil will determine the inductance; typically, around 10-15 turns of wire with a diameter of about 1 cm will yield approximately 1 µH. Use an inductance meter to measure and adjust the number of turns or the coil dimensions as needed to achieve the desired inductance. Ensure the wire is of suitable gauge for your intended application.